Dual battery setups and mounts

Been searching here and not finding info, but saw a pic a while back. Don’t recall where I saw it at though. I am considering putting in a second battery in my 08 SR5. Curious for those of you whose have done this, can you post up some pictures and the info related to the install please?

Got quite a bit of room in the engine compartment on the passenger side but not a lot of height, at least not enough for the stock battery height. Was also considering a CAI but that takes up a lot of room and would be where I’d think the battery would go instead.
 
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It is a tight fit but not too bad, make sure you get your terminal orientation right. You want the positive towards the engine.

I did mine years ago, and it's been great, but I have plans to tear it all out and upgrade various items because I can't leave good enough alone.

Existing:
Dirty Parts Tray
Blue Sea ACR
Blue Sea Fuse Blocks (engine bay and interior sub panel)
Blue Sea Low Voltage Disconnect
Cut and crimped cables to length
Genasun MPPT Solar Charge Controller
Bunch of Anderson Quick Disconnects
Bunch of other add-on and accessories

uFOxKGv.jpg

crUmrTu.jpg

y8TAqKm.jpg


I did a write up on the ACR here:
https://www.toyota-4runner.org/engi...cr-automatic-charging-relays.html#post2642084

I originally bought the 7610 but later changed to 7611.

Upgrade:
Relocate battery and upgrade to a compact lithium setup.
Delete traditional fuse block for Switch Pro 9100
Delete ACR for a DC-DC charger - Victron Energy
Delete Genasun MPPT for Victron MPPT for monitoring and reporting capability.

If all that provides me with enough room where the old battery went, I will install 100% duty cycle compressor from Hummer central air system.

gVTzvQe.jpg
 
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It is a tight fit but not too bad, make sure you get your terminal orientation right. You want the positive towards the engine.

I did mine years ago, and it's been great, but I have plans to tear it all out and upgrade various items because I can't leave good enough alone.

Existing:
Dirty Parts Tray
Blue Sea ACR
Blue Sea Fuse Blocks (engine bay and interior sub panel)
Blue Sea Low Voltage Disconnect
Cut and crimped cables to length
Genasun MPPT Solar Charge Controller
Bunch of Anderson Quick Disconnects
Bunch of other add-on and accessories

uFOxKGv.jpg

crUmrTu.jpg

y8TAqKm.jpg


I did a write up on the ACR here:
https://www.toyota-4runner.org/engi...cr-automatic-charging-relays.html#post2642084

I originally bought the 7610 but later changed to 7611.

Upgrade:
Relocate battery and upgrade to a compact lithium setup.
Delete traditional fuse block for Switch Pro 9100
Delete ACR for a DC-DC charger - Victron Energy
Delete Genasun MPPT for Victron MPPT for monitoring and reporting capability.

If all that provides me with enough room where the old battery went, I will install 100% duty cycle compressor from Hummer central air system.

gVTzvQe.jpg

Looks good, I appreciate your information, thank you for sharing! When you relocate your battery, where are you moving it to? Which new battery are you looking at? Since you’ve been through this I’d like to consider your changes you’re planning on implementing. Seems like it’s a little bigger job and more parts than I was initially anticipating but like the additional and failsafes and like to do it right the first time.

I put a second battery in a truck years ago but all I did was run it in series and had enough room in the engine bay to butt it up against the original. Worked fine for what I needed it for.
 
Looks good, I appreciate your information, thank you for sharing! When you relocate your battery, where are you moving it to? Which new battery are you looking at? Since you’ve been through this I’d like to consider your changes you’re planning on implementing. Seems like it’s a little bigger job and more parts than I was initially anticipating but like the additional and failsafes and like to do it right the first time.

I put a second battery in a truck years ago but all I did was run it in series and had enough room in the engine bay to butt it up against the original. Worked fine for what I needed it for.

I would consider this to be somewhat of a minimum build for most people who "just want it to work".

My first dual battery build was in my Silverado. It was two batteries with a manually operated switch between them. There was a lot of "remembering" to do something, and when I forget, I still killed the starter battery or forgot to charge.

The only thing new I did was add the BlueSea ACR (inexpensive and good) to automate the switch task. When the car is running, both batteries are connected. When it is off, the 2nd is disconnected to preserve the starer.

The low voltage disconnect was an optional add to protect the health of the 2nd battery from draining it to the point of death.

Everything appears to have done it's job. I did this project in 2016 and both the originally batteries are still in the 4Runner. I didn't buy anything special either, just regular $100 starter batteries and didn't go too deep on discharge.

I don't know what my new plans are, but I plan on doing something new/different just to show what can be done.

I don't need a full size battery up front, I don't do any winching or activities that require high current cabling. In the 5 years I had this, the only thing I run that really needs a 2nd battery is the fridge/freezer.

I will most likely build a custom lithium battery pack that will fit under the fridge. Similar to a drawer system, but just a low profile base for the fridge that can be moved.

I am building this with my 5th gen in mind... One of my plans was to size the DC-DC charger to about 7-10 amps, which would allow the use of the factory rear existing 12v accessory plug. The primary goal being that I could use this as a "plug and play" dual battery setup that requires zero modification to the 4Runner and functions no different than an on-board install.
 
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No room in engine bay for secondary battery due to arb air compressor for air locker mounted in that area. So decided to go this route the National Luna Portable Power Pack.

90ab5ea6acb6e8b4a4bcce8b7bf8bd96.jpg

8a1d9e2839a2a91e0746b6614803b92c.jpg



Sent from my iPhone using Tapatalk
 
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I love desert off-road. Really moving there in the 4Runner.

Was than an APRS squawking in the background?
 
I love desert off-road. Really moving there in the 4Runner.

Was than an APRS squawking in the background?


Yes we were using simplex freq. and using the local area repeater freq. dialed in also for emergencies.


Sent from my iPhone using Tapatalk
 
I’ve got a group 31M house battery where the original battery was (in a Pelfreybilt cage left over from my 2016 tacoma) and a group 34 vehicle battery in an Off Grid Engineering set up on the PS rear. Took a bit of routing work to relocate main battery, but allowed for a much larger amp hour house battery. Using a DC to DC charger to keep house battery full. Both batteries are AGM and I did the resistor mod to increase charging voltage for AGM truck battery to fully charge.
 

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Looking at both the differences in how someone does this for a v6 and v8 are subtle, but still somewhat significant.
 
Anyone ever use a Group 65 battery under the hood? I have a spare one from an old project that I'd like to install in my new V8.

Thanks
-Rob
 

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